ref: 2e0a3ec2d5b2252ebab15e28998bac82c33e8edd dir: /sys/src/cmd/plot/libplot/erase.c/
#include "mplot.h" void erase(void){ m_swapbuf(); m_clrwin(clipminx, clipminy, clipmaxx, clipmaxy, e1->backgr); }